Matco master cylinder leak

Kokemiller · #1 07-18-2009, 11:23 AM

Just had my first maintenance issue on my yet to fly 9a. noticed brake fluid building up in the area where the piston goes into the master cylinder, cleaned it up a few times and in a few days it would pool up again. Vans sent a rebuild kit free of charge and I installed it last night, bled the lines, and so far so good. Just wandering if these Matco master cylinders have cronic leak issues or if it was just bad luck.

frankh · #2 07-18-2009, 12:14 PM

Personally never heard of another one leaking. Mine are fine at 350 hours ish.

Frank

Randy Hooper · #3 07-18-2009, 04:34 PM

Both of my cylinders leaked from the beginning as you describe. I went by Van's Sun-N Fun booth to ask the question to see if this has been an issue. I spoke with Gus and he said I had probablely let some shavings get into the master cylinder. I could not imangine this happening to both master cylinders. He suggested I order their rebuild kit.
I contacted Matco. They said that if the master cylinders had set on the shelf for a while, the fluid they use in assymbley could dry and cause a leak.
I ordered two kits from Matco at about the same price as one from Van's. It did lack an aluminum piston that I did not need.
Now I have one that does not leak and one that does.
I know of one Yak 52TW that has the same issue and will be watching this thread to find the answer.

rgrigson · #4 07-25-2009, 09:32 PM

I just hooked up my master cylinders in my -8 and the left started to leak immediately at the same location. I havn't flown yet. I'll contact Vans and shoot for a replacement.

Robert Grigson
RV-8

vic syracuse · #5 07-26-2009, 08:01 AM

I also have one leaking at 190 hours. Am ordering the rebuild kit from Van's.

Vic

Randy Hooper · #6 07-26-2009, 10:27 AM

I found the Matco tent this morning and am planning to visit with them tomorrow.
I will try and post there coments.

PCHunt · #7 07-26-2009, 11:21 AM

I just rebuilt my brake system, and added right-side brakes. I used Grove cylinders, and they are top-of-the-line! Adjustable, also, so it is easy to get the right "tilt" on the brake pedals.

Very happy with Grove!!!

Randy Hooper · #8 07-29-2009, 01:27 PM

I just returned from OSH. While there I spoke to a Matco rep about my ongoing problem. After answering a few questions he wanted to walk to RV parking for a look at my installation. Examining the master cylinders he felt the shafts could possibly have an imperfect finish. He took my address and said they would try and ship a new set same day.
It is a blood running to my head pain to remove and replace the cylinders, but I am very pleased with their attention and support.

dbiddle · #9 12-28-2009, 12:00 PM

I have the same thing, on the left, after 8 years, about 600 hours. Rebuilt the cylinder but still leaks. The shaft has wear (a groove) and I believe that is where the leak is. I want to replace the shaft. Matco Site shows several shafts.
http://www.matcomfg.com/MasterCylind...46.html?Pos=54
I believe it is the MC-4G but it could be but it could be the MC-4A. I don't have this apart or even where I can see it now. Anybody know for sure?

dbiddle · #10 12-28-2009, 01:04 PM

Looking at my pictures and the available shafts, I ordered the MC-4E shaft. I hope that is correct. Here is the link:
http://www.matcomfg.com/SHAFTMC4F-idv-3079-46.html